cm:Concept: us-gaap:ReinsuranceReceivablesCaseBasis
| Reinsurance Recoverables, Case Basis |
| us-gaap:ReinsuranceReceivablesCaseBasis |
| The sum for all reinsurance arrangements of the known and estimated amount recoverable as of the balance sheet date from a given reinsurer for claims paid or incurred by the ceding insurer and associated claims settlement expenses for each reinsurance arrangement (or, the sum of all cases determined individually, probably applying different assumptions to each arrangement). |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:ReinsuranceReceivablesCaseBasis |